I am working on something big. You are going to want this on Weather Channel Weather Geeks

He couldn't really say much at that time, but he was right. His new study was recently published in the journal Nature Climate Change, a very high-impact scholarly journal. The NOAA press release says the paper argues that by 2030 electricity in the United States could be provided primarily by wind and the sun. Ummmm, wait, that is 14 years away!

A snapshot of wind energy potential across the United States in 2012. (via Chris Clack/CIRES). Source: NOAA Press Release

Carbon dioxide emissions from electricity generation are a major cause of anthropogenic climate change. The deployment of wind and solar power reduces these emissions, but is subject to the variability of the weather. In the present study, we calculate the cost-optimized configuration of variable electrical power generators using weather data with high spatial (13-km) and temporal (60-min) resolution over the contiguous US. Our results show that when using future anticipated costs for wind and solar, carbon dioxide emissions from the US electricity sector can be reduced by up to 80% relative to 1990 levels, without an increase in the levelized cost of electricity.

How do the authors envision this happening? MacDonald and his team developed a model to try to scale wind and solar power up to mitigate the inherent intermittent nature of renewable sources. They theorized that by scaling up the renewable energy generation system to the scale of weather systems they can take advantage of the fact that wind is blowing or the sun is shining somewhere in the U.S.

Their model evaluates a "basket" or mix of different energy sources then compares reliability, emissions, and affordability. They found that low-emissions and low-cost are not mutually exclusive. Co-author Christopher Clack, a mathematician and physicist at University of Colorado's Cooperative Institute for Research in Environmental Sciences told NOAA,

The model relentlessly seeks the lowest-cost energy, whatever constraints are applied....And it always installs more renewable energy on the grid than exists today.

The NOAA press release gives the following example,

Even in a scenario where renewable energy costs more than experts predict, the model produced a system that cuts CO2 emissions 33 percent below 1990 levels by 2030, and delivered electricity at about 8.6 cents per kilowatt hour. By comparison, electricity cost 9.4 cents per kWh in 2012.If renewable energy costs were lower and natural gas costs higher, as is expected in the future, the modeled system sliced CO2 emissions by 78 percent from 1990 levels and delivered electricity at 10 cents per kWh. The year 1990 is a standard scientific benchmark for greenhouse gas analysis.

Ok, but how can this be done from an infrastructure standpoint? Macdonald and his team configured their model to implement various solutions. The model exclusively chose a high-voltage direct-current transmission grid (HVDC) to supplement the current electrical grid. HVDC lines reduces energy losses over long distances and are used in other places around the world. MacDonald says an HVDC grid is analogous to how the Interstate Highway system was a transformation of the U.S. economy. He says,

With an ‘interstate for electrons’, renewable energy could be delivered anywhere in the country while emissions plummet........An HVDC grid would create a national electricity market in which all types of generation, including low-carbon sources, compete on a cost basis. The surprise was how dominant wind and solar could be.

This study pushes the envelope.......It shows that intermittent renewables plus transmission can eliminate most fossil-fuel electricity while matching power demand at lower cost than a fossil fuel-based grid - even before storage is considered